[java 백준] 실버 3/ 9613번 GCD 합

https://www.acmicpc.net/problem/9613

9613번: GCD 합

 

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
 
public class Main {
    
    public static long gcd(long a, long b) {
        if (b == 0) {
            return a;
        } else {
            return gcd(b, a % b);
        }
    }
 
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb = new StringBuilder();
        int num = Integer.parseInt(br.readLine());
        long[] totals = new long[num];
        for (int i = 0; i < num; i++) {
            long total = 0;
            String s = br.readLine();
            String[] arr = s.split(" ");
 
            for (int j = 1; j <= arr.length - 2; j++) {
                for (int k = j + 1; k <= arr.length - 1; k++) {
                    total += gcd(Long.parseLong(arr[j]), Long.parseLong(arr[k]));
                }
            }
            totals[i] = total;
        }
        for (int i = 0; i < num; i++) {
            System.out.println(totals[i]);
        }
 
    }
 
}

 

 

total변수를 long으로 두는게 핵심이다!!